1) The document examines the seismic response of flat slab and grid slab buildings through dynamic analysis.
2) Two flat slab buildings and their inherent seismic resistance are evaluated when designed only for wind loads.
3) The conclusions show that while specific design parameters like drift, base shear, and overturning moment exceed wind design values, the structures have sufficient inherent capacity to resist moderate seismic loads if they satisfy wind criteria.
4) Dynamic analysis is performed to determine design seismic forces and their distribution for evaluation.
Parametric Study on Diagrid Structural System with and without Shear WallsAI Publications
Among the various lateral load resisting systems of the tall structures, diagrid structural system is a unique structural system and found effective compared to other bracing systems, which is increasingly popular from the past decades. The diagrids are perimeter structural configurations characterized by a grid of diagonal members which are involved both in gravity and in lateral load resistance. The diagrid structure ensures the overall stiffness and strength of the building only engaging the diagonal members in a purely axial behaviour and fully braces the interior gravity columns for stability only at joints of diagrid. The intermediate floors, are not laterally restrained by the global behaviour of the diagrid system, means if diagonals are continuous throughout the module height, the floors would derive a certain degree of lateral stiffness only from the flexural stiffness of the diagrids. Although diagrid system is good enough to perform well in lateral load resisting compare to other simple frame and shear wall building, we can combined the diagrid structure with shear walls for optimum design. The present study aimed to understand the behaviour of the diagrid structural system with shear walls at core. For this study a regular square plan of 30m × 30m diagrid structure considering different storey module (i.e. 4, 6, 8 & 12) with and without core Shear Walls is modelled and analyzed. For minimum displacement and drift different plan shape of shear wall are taken and one of them with optimum results is used for further analysis. Then behaviour of diagrid structure with and without shear wall along the height is also studied considering 24, 36 and 48 storey. ETABS software is used for modelling and analysis. Parameters such as inter storey drift-ratio, storey displacement, base shear and reduction in lateral load on diagrid are taken into consideration.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Parametric Study on Diagrid Structural System with and without Shear WallsAI Publications
Among the various lateral load resisting systems of the tall structures, diagrid structural system is a unique structural system and found effective compared to other bracing systems, which is increasingly popular from the past decades. The diagrids are perimeter structural configurations characterized by a grid of diagonal members which are involved both in gravity and in lateral load resistance. The diagrid structure ensures the overall stiffness and strength of the building only engaging the diagonal members in a purely axial behaviour and fully braces the interior gravity columns for stability only at joints of diagrid. The intermediate floors, are not laterally restrained by the global behaviour of the diagrid system, means if diagonals are continuous throughout the module height, the floors would derive a certain degree of lateral stiffness only from the flexural stiffness of the diagrids. Although diagrid system is good enough to perform well in lateral load resisting compare to other simple frame and shear wall building, we can combined the diagrid structure with shear walls for optimum design. The present study aimed to understand the behaviour of the diagrid structural system with shear walls at core. For this study a regular square plan of 30m × 30m diagrid structure considering different storey module (i.e. 4, 6, 8 & 12) with and without core Shear Walls is modelled and analyzed. For minimum displacement and drift different plan shape of shear wall are taken and one of them with optimum results is used for further analysis. Then behaviour of diagrid structure with and without shear wall along the height is also studied considering 24, 36 and 48 storey. ETABS software is used for modelling and analysis. Parameters such as inter storey drift-ratio, storey displacement, base shear and reduction in lateral load on diagrid are taken into consideration.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis of rc frame with and without masonry infill wall with different stif...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A Study of Reduced Beam Section Profiles using Finite Element AnalysisIOSR Journals
Abstract: Reduced beam section (RBS) is one of the several connection types, which is economical and
popular for use in new steel moment frame structures in seismic zone. To form RBS connection, some portion of
the beam flanges at a short distance from column face is purposefully trimmed so that the yielding and plastic
hinge occurs within this area of flanges. Use of RBS connection is found advantageous due to: a) the shear
force in the panel zone is reduced; b) the force demand in column continuity plates i.e. stiffeners are reduced;
and c) strong-column – weak-beam requirement is satisfied. Although, radius cut RBS is qualified by
ANSI/AISC, FEMA codes, various flange cut shapes like constant, tapered, radius cut, drilled holes are possible
to reduce the cross sectional area of beam flanges. The purpose of this study is to understand behavior of RBS
beam-to-column moment connections for various flange cut geometries. This document represents nonlinear
finite element analysis of the connection models performed using the computer program, ANSYS/Multiphysics
Keywords - Steel structures, steel connections, reduced beam section, RBS profiles
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including...IOSR Journals
Masonry infill is considered as a non-structural element in all type of buildings where masonry use.
But, masonry infill walls are mainly used to increase initial stiffness and strength of reinforced concrete (RC)
frame buildings. This Open First storey is also termed as “Soft Storey”. The upper storeys have brick infilled
wall panels with various opening percentage in it. In many cities of India, it is very common to leave the first
storey of masonry infilled reinforcement concrete (RC) frame building open preliminary to generate parking
space or any other usage in the first storey. Such buildings are highly undesirable in seismically active areas. In
the present study, it is an attempt to access the performance of masonry infilled reinforced concrete (RC) frames
with soft storey of with and without opening. In this paper, symmetrical frame of college building (G+5) located
in seismic zone-III is considered by modelling of initial frame. According to FEMA-273, & ATC-40 which
contain the provisions of calculation of stiffness of infilled frames by modelling infill as“Equivalent Diagonal
Strut Method”. Therefore, the infill panels are modelled as equivalent diagonal strut method. The error
involved in modelling such buildings as neglecting the presence of infills in the upper storeys, is brought out
through the study of an example building with different analytical models. This linear static analysis is to be
carried out on the models such as Strut frame with 15%, 20%, & 25% centre &corner opening, which is
performed by using computer software STAAD-Pro from which different parameters are computed. In which it
shows that how infill panels increase the stiffness of the structure. While the increase in the opening percentage
leads to a decrease on the lateral stiffness of infilled frame. This paper highlights the importance of the presence
of the open first storey in the analysis of the building
Finite ElementAnalysis of Doubly Curved Thin Concrete ShellsHARISH B A
thin shell is a “Three-dimensional spatial structure made up of one or more curved surfaces whose
thickness is small compared to their other dimensions”. Shells belong to the class of stressed skin structures which,
because of their geometry and small flexural rigidity of the skin, tend to carry loads primarily by direct stresses acting in
their plane. The shells are subjected to pure membrane state of stress, under appropriate loading and boundary
condition the resulting bending and twisting moments are either zero or small which may be neglected. The coordinates
of funicular shells are determined by masonry mould method by developing a computer program. In this study doubly
curved thin shells are analysed using finite element software SAP 2000. Doubly curved shells which are in square plan
having 10mX10m and 15mX15m are considered and shells in rectangular plan having dimensions 10mX15m
and 15mX20m are considered. The behavior of shells under self-weight, live load varying from 0-20KN/m (UDL) is
obtained. In this case study deflection curves, membrane stress and stress contour diagram are obtained. It is observed
that with the increase in rise and thickness of funicular shell the deflection are reduced. The membrane stresses
decreases with the increase in rise and thickness of concrete funicular shell. The aim of this study is to develop shells of
different sizes and investigation is done on the shells by finite element analysis under given uniformly distributed load,
to find out the behavior of shells in various cases using standard software, Structural Analysis Package (SAP 2000).
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Behaviour of 3 d rc frames with masonry infill under earthquake loads an ana...eSAT Journals
Abstract Moderate and astringent earthquakes have struck different places in the world, causing rigorous damage to reinforced concrete
structures. The bond between the structural elements and masonry in-fills of the building is habitually effected by Earthquake. The
voids between horizontal and vertical resisting elements of the building frame is filled by Masonry in-fills. An infill wall enhances
considerably the strength and rigidity of the structure. It has apperceived that frames with in-fills have more vigor and rigidity
compared to the bare frames Hence this study is about the demeanor of 3D-RC frames with and without masonry in-fills utilizing
E-TABS. parameters were studied like displacement, lateral load distribution, stiffness and overturning moment of the frames and
it is concluded that, the in-fill walls are needed to be considered while designing phase of the structures.
Keywords: Earthquake load, 3D RC Frame, Masonry In-Fill
Analysis of rc frame with and without masonry infill wall with different stif...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A Study of Reduced Beam Section Profiles using Finite Element AnalysisIOSR Journals
Abstract: Reduced beam section (RBS) is one of the several connection types, which is economical and
popular for use in new steel moment frame structures in seismic zone. To form RBS connection, some portion of
the beam flanges at a short distance from column face is purposefully trimmed so that the yielding and plastic
hinge occurs within this area of flanges. Use of RBS connection is found advantageous due to: a) the shear
force in the panel zone is reduced; b) the force demand in column continuity plates i.e. stiffeners are reduced;
and c) strong-column – weak-beam requirement is satisfied. Although, radius cut RBS is qualified by
ANSI/AISC, FEMA codes, various flange cut shapes like constant, tapered, radius cut, drilled holes are possible
to reduce the cross sectional area of beam flanges. The purpose of this study is to understand behavior of RBS
beam-to-column moment connections for various flange cut geometries. This document represents nonlinear
finite element analysis of the connection models performed using the computer program, ANSYS/Multiphysics
Keywords - Steel structures, steel connections, reduced beam section, RBS profiles
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including...IOSR Journals
Masonry infill is considered as a non-structural element in all type of buildings where masonry use.
But, masonry infill walls are mainly used to increase initial stiffness and strength of reinforced concrete (RC)
frame buildings. This Open First storey is also termed as “Soft Storey”. The upper storeys have brick infilled
wall panels with various opening percentage in it. In many cities of India, it is very common to leave the first
storey of masonry infilled reinforcement concrete (RC) frame building open preliminary to generate parking
space or any other usage in the first storey. Such buildings are highly undesirable in seismically active areas. In
the present study, it is an attempt to access the performance of masonry infilled reinforced concrete (RC) frames
with soft storey of with and without opening. In this paper, symmetrical frame of college building (G+5) located
in seismic zone-III is considered by modelling of initial frame. According to FEMA-273, & ATC-40 which
contain the provisions of calculation of stiffness of infilled frames by modelling infill as“Equivalent Diagonal
Strut Method”. Therefore, the infill panels are modelled as equivalent diagonal strut method. The error
involved in modelling such buildings as neglecting the presence of infills in the upper storeys, is brought out
through the study of an example building with different analytical models. This linear static analysis is to be
carried out on the models such as Strut frame with 15%, 20%, & 25% centre &corner opening, which is
performed by using computer software STAAD-Pro from which different parameters are computed. In which it
shows that how infill panels increase the stiffness of the structure. While the increase in the opening percentage
leads to a decrease on the lateral stiffness of infilled frame. This paper highlights the importance of the presence
of the open first storey in the analysis of the building
Finite ElementAnalysis of Doubly Curved Thin Concrete ShellsHARISH B A
thin shell is a “Three-dimensional spatial structure made up of one or more curved surfaces whose
thickness is small compared to their other dimensions”. Shells belong to the class of stressed skin structures which,
because of their geometry and small flexural rigidity of the skin, tend to carry loads primarily by direct stresses acting in
their plane. The shells are subjected to pure membrane state of stress, under appropriate loading and boundary
condition the resulting bending and twisting moments are either zero or small which may be neglected. The coordinates
of funicular shells are determined by masonry mould method by developing a computer program. In this study doubly
curved thin shells are analysed using finite element software SAP 2000. Doubly curved shells which are in square plan
having 10mX10m and 15mX15m are considered and shells in rectangular plan having dimensions 10mX15m
and 15mX20m are considered. The behavior of shells under self-weight, live load varying from 0-20KN/m (UDL) is
obtained. In this case study deflection curves, membrane stress and stress contour diagram are obtained. It is observed
that with the increase in rise and thickness of funicular shell the deflection are reduced. The membrane stresses
decreases with the increase in rise and thickness of concrete funicular shell. The aim of this study is to develop shells of
different sizes and investigation is done on the shells by finite element analysis under given uniformly distributed load,
to find out the behavior of shells in various cases using standard software, Structural Analysis Package (SAP 2000).
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Behaviour of 3 d rc frames with masonry infill under earthquake loads an ana...eSAT Journals
Abstract Moderate and astringent earthquakes have struck different places in the world, causing rigorous damage to reinforced concrete
structures. The bond between the structural elements and masonry in-fills of the building is habitually effected by Earthquake. The
voids between horizontal and vertical resisting elements of the building frame is filled by Masonry in-fills. An infill wall enhances
considerably the strength and rigidity of the structure. It has apperceived that frames with in-fills have more vigor and rigidity
compared to the bare frames Hence this study is about the demeanor of 3D-RC frames with and without masonry in-fills utilizing
E-TABS. parameters were studied like displacement, lateral load distribution, stiffness and overturning moment of the frames and
it is concluded that, the in-fill walls are needed to be considered while designing phase of the structures.
Keywords: Earthquake load, 3D RC Frame, Masonry In-Fill
Apresentação de lançamento da obra Vida Profissional: Lições para uma Jornada de Excelência, em Natal - RN. Livraria Saraiva Mega Store - Shopping Midway Mall.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Seismic Response of Structure with Single Coreijtsrd
Shear walls and outriggers have been used so far to resist the seismic waves of earthquake and heavy winds actions. The complete failure of the structures that has occurred in the past due to catastrophic earthquake may be avoided with the use of shear wall in the structure. The study is concerned with the use of shear wall as a single core in structure that will resist the seismic waves of earthquake. In the present study analysis of RCC building has been carried out by changing the locations of shear walls in the building. The seismic analysis performed is linear dynamic response spectrum analysis using the well known analysis and design software ETABS 16.2.0. Seismic performance of the building has been investigated based on parameters such as strorey drift, base shear and storey displacement. Belsare Sumit Bandopanth | Dilip Budhlani "Seismic Response of Structure with Single Core" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-3 , April 2020, URL: https://www.ijtsrd.com/papers/ijtsrd30851.pdf Paper Url :https://www.ijtsrd.com/engineering/civil-engineering/30851/seismic-response-of-structure-with-single-core/belsare-sumit-bandopanth
Cost Comparative Study On Steel Frame Folded Plate Roofing System Vs Conventi...IJERA Editor
Due to ever-increasing of construction materials, it becomes the foremost duty of a civil engineer to design economical and durable structures. In this project an attempt has been made to compare the cost of two types of roofing systems viz. conventional truss roofing system and steel frame folded plate roofing system. The steel frame folded plate roofing system, though found to be economical, is not widely practiced in India due to lack of knowledge regarding its analysis and design. On contrary to it, the conventional truss roofing system still remains as the widely adopted method of roofing for different types of buildings due to the available literature on its analysis, design and construction. The analysis and design of conventional truss roofing system and folded plate roofing system have been carried out for various spans. The analysis is carried out in STAAD.Pro 2004, which is based on stiffness method. Load calculations and design done manually, based on IS:875-1987, IS:800-1984 & SP:38(1987)
OPTIMAL DIAGRID ANGLE TO MINIMIZE DRIFT IN HIGH-RISE STEEL BUILDINGS SUBJECTE...IAEME Publication
Nowadays, tending to use super high-rise steel buildings has increased the need for finding efficient and economical lateral load resisting systems. The diagrid structural system is widely used for medium- and super-high-rise buildings due to its structural efficiency. The aim of this study was to find the optimal diagrid angle to minimize the lateral drift in high-rise building. Five different diagrid angle configurations (27o, 45o, 56o, 72o, and 81o) have been considered for 24, 48 and 72-storey steel buildings. The results were tabulated by performing finite element analysis using ETABS version 15 in the form of lateral displacement and storey drift. It is shown that the optimal diagrid angle is smaller than 56o for 24-storey model, and between (56o- 72o) for 48-storey model, and 72o for 72-storey model.
Evaluation of Flat Slab by Varying Percentage of Infill Wall in RC Building U...ijtsrd
In the area of high seismicity the conventional slabs are become uneconomical due increase in design requirement to tackle additional seismic loads. The use of deep beams, increased column sections etc led to costly frame work. Moreover masonry infill wall effect is not incorporated in the design of conventional slab building frames, which led to unsafe or uneconomical design. These panels are used to fill gaps between the frames of building. Under seismic action these walls increases the strength and stiffness and reduces the time period by increasing the seismic mass of the building. This hinders the ductility requirement of the conventional frames which may lead to brittle failure under seismic action. To avoid this effect the flat slab systems are used. The flat slabs are the beamless frame having lower lateral stiffness, high storey drift, and are more flexible. But these are more susceptible to failure under seismic action.Hence to avoid the failure of flat slab structure under seismic action, some lateral resistance structural elements are used in order to increase stiffness, reduce storey drift, lateral displacement thereby improving the lateral resistance of the system.In the present study an attempt is made to analyze and study the various multi storied reinforced concrete flat slab building frames with several percentage of infill wall considering the lateral resistance of flat slabs by evaluating parameters, subjected to seismic loading. A number of flat slab building frames are analyzed by varying the percentage of infill wall 0 , 50 , 80 and 100 to evaluate parameters affected by the addition of infill wall in the flat slab. The results obtained by analysis are used to study and compare the effects of variable percentages of infill wall on the lateral resistance of flat slabs by varying storey height. The several parameters are compared for the lateral resistance assessment of flat slabs. The effect of masonry infill wall on flat slab frame in studied in terms of several parameters for the lateral resistance of the flat slab under seismic actions. Jitendra Perwal | Dr. Rajeev Singh Parihar | Abhay Kumar Jha "Evaluation of Flat Slab by Varying Percentage of Infill Wall in RC Building Using STAAD-Pro" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-1 , December 2021, URL: https://www.ijtsrd.com/papers/ijtsrd47877.pdf Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/47877/evaluation-of-flat-slab-by-varying-percentage-of-infill-wall-in-rc-building-using-staadpro/jitendra-perwal
Performance Evaluation of Flat Slab by Varying Percentage of Infill Wall in R...ijtsrd
In the zone of high seismicity the ordinary chunks are gotten uneconomical due increment in plan prerequisite to handle extra seismic burdens. The utilization of profound shafts, expanded segment areas and so forth prompted expensive edge work. In addition workmanship infill divider impact isnt fused in the plan of traditional section building outlines, which prompted perilous or uneconomical plan. These boards are utilized to fill holes between the casings of building. The level pieces are the beamless casing having lower horizontal solidness, high story float, and are more adaptable. In any case, these are more defenseless to disappointment under seismic activity. Thus to keep away from the disappointment of level chunk structure under seismic activity, some parallel opposition basic components are utilized so as to build firmness, lessen story float, horizontal relocation along these lines improving the sidelong obstruction of the framework. In the current examination an endeavor is made to break down and study the different multi celebrated fortified solid level piece building outlines with a few level of infill divider thinking about the sidelong opposition of level sections by assessing boundaries, exposed to seismic stacking. Various level piece building outlines are investigated by fluctuating the level of infill divider 0 , half, 80 and 100 to assess boundaries influenced by the expansion of infill divider in the level section. The outcomes got by examination are utilized to study and look at the impacts of variable rates of infill divider on the sidelong obstruction of level chunks by shifting story tallness. The few boundaries are thought about for the horizontal opposition evaluation of level chunks. The impact of stone work infill divider on level piece outline in concentrated as far as a few boundaries for the sidelong obstruction of the level chunk under seismic activities. Manish Kumar | Dr. Shubha Agarwal "Performance Evaluation of Flat Slab by Varying Percentage of Infill Wall in RC Building" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-6 , October 2020, URL: https://www.ijtsrd.com/papers/ijtsrd33505.pdf Paper Url: https://www.ijtsrd.com/engineering/civil-engineering/33505/performance-evaluation-of-flat-slab-by-varying-percentage-of-infill-wall-in-rc-building/manish-kumar
IRJET- Multi Cornered Thin Wall Sections for Crashworthiness and Occupant Pro...
Ap24275280
1. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
“Dynamic Analysis Of Special Moment Resisting Frame Building
With Flat Slab And Grid Slab”
*Sandesh D. Bothara*, Dr.Valsson Varghese**
*(P.G. Student (M-Tech- Structure), Department of Civil Engineering, KDKCE, Nagpur-440009, Maharashtra,
India)
** (Professor, Department of civil Engineering KDKCE, Nagpur-440009, Maharashtra, India)
ABSTRACT
A popular form of concrete building construction uses a A reinforced concrete flat slab, also called as beamless slab, is
flat concrete slab (without beams) as the floor system. This a slab supported directly by column without beams. A part of
system is very simple to construct, and is efficient in that it the slab bounded on each of the four sides by centre line of the
requires the minimum building height for a given number column is called panel. The flat slab is often thickened closed
of stories. Unfortunately, earthquake experience has to supporting columns to provide adequate strength in shear
proved that this form of construction is vulnerable to and to reduce the amount of negative reinforcement in the
failure, when not designed and detailed properly, in which support region. The thickened portion i.e. the projection below
the thin concrete slab fractures around the supporting the slab is called drop or drop panel. In some cases, the section
columns and drops downward, leading potentially to a of column at top, as it meets the floor slab or a drop panel, is
complete progressive collapse of a building as one floor
cascades down onto the floors below.
Grid floor system consisting of beam spaced at
regular intervals in perpendicular directions, monolithic
with slab .They are generally employed for architectural
reasons for large room such as, auditoriums, theaters halls,
show room of shops. Analysis and Design of flat slabs are
still the active areas of research and there is still no general
agreement on the best design procedure. The present day
Flat slab with drop & column head structure
Indian Standards Codes of Practice outline design
procedures only for slabs with regular geometry and
layout. But in recent times, due to space crunch, height
limitations and other factors, deviations from a geometry
and regular layout are becoming quite common. Also
behavior and response of flat slabs during earthquake is a
big question.
KEYWORD :- Flat slab, grid slab, storey drift
SCOPE OF STUDY
The lateral behavior of a typical flat slab building which is
designed according to I.S. 456-2000 is evaluated by means of
dynamic analysis. The inadequacies of these buildings are
discussed by means of comparing the behavior with that of Typical flat slab
conventional flat slab & Grid slab system is selected for this
purpose. To study the effect of drop panels on the behavior of
flat slab during lateral loads, Zone factor and soil conditions –
the other two important parameters which influence the
behavior of the structure, are also covered. Software ETABS
is used for this purpose. In this study between the number of
stories, zone and soil condition is developed
1. INTRODUCTION
1.1 FLAT SLAB
275 | P a g e
2. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
DESIGN OF FLAT SLAB
Method of Design:
Two approximate methods are adopted by the codes
for design of flat slab. These methods can be used provided
the limitation.
The two design methods are:
a) The direct design method
b) The equivalent frame method
1.2 GRID SLAB
Grid floor systems consisting of beams spaced at regular
interval in perpendicular directions, monolithic with slab.
They are generally employed for architectural reasons for
large rooms such as auditoriums, theatre halls, show rooms of
shop where column free spaced void formed in the ceiling is
advantageously utilized for concealed architectural lighting.
The sizes of the beam running in perpendicular directions are
Floor system generally kept the same. Instead of rectangular beam grid, a
Enlarged so as to increase primarily the perimeter of the diagonal
critical section for shear force hence increasing the capacity of
the slab resisting two way shear and to reduce negative ANALYSIS OF GRID SLAB
bending moment at such enlarged or flared portion of capital. 1. Approximate Methods
2. Analysis of grid floor by plate load theory
METHODS PLANNIG STAGE
General 1. Plan dimensions 25.2 m x 42 m (Center to
This report examines the seismic response of Center dist)
structures. The findings are of importance in the evaluation of 2. Length in X- direction 42 m
the inherent seismic resistance of such structures, designed
only for wind-induced lateral forces, and in the evaluation on 3. Length in Y- direction 25.2 m
the effect of implementation of specific design requirements.
The conclusions, based on the examination of two flat slab 4. Floor to floor height 3.6 m
structures, show that although specific design parameters
(drift, base shear, overturning moment) exceed those induced 5. No. of Stories 9
by static wind pressure, the inherent capacity structure may be
sufficient to resist moderate seismic excitation if the structure 6. Total height of 32.4 m
satisfy wind design criteria Building
Dynamic analysis shall be performed to obtain the design
7. Slab Thickness 250 mm
seismic forces and its distribution to different levels along
the height of building and to the various lateral load
resisting element. 8. Thickness of the drop 100 mm
Method of Dynamic Analysis: 9. Width of drop 3000 mm
Building with regular or nominally irregular plan
configuration may be modeled as a system of masses lumped 10. Edge Beam 400 x 900 mm
at floor levels with each mass having one degree of
freedom, that of lateral displacement in the direction under 11. Size of the Column 1-3 story 850 x 850 mm
consideration. Undamped free vibration analysis of entire
building modeled as spring – mass model shall be 4-6 story 750 x 750 mm
performed using appropriate masses and elastic stiffness of the
structural system to obtain natural periods (T) and mode 7-9 story 600 x 600 mm
shapes {f} of those of its modes of vibration that needs to be
considered. The number of modes to be used should be such
that the sum of total of modal masses of all modes considered 12. Grade of concrete M 25
is at least 90% of total seismic mass
13. Grade of Steel Fe 415
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3. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
14. Panel Dimensions 8.4 x 8.4 m 1.2 EQY + 1.2 DL + 0.3 LL
-1.2EQY +1.2 DL + 0.3 LL
15. Width of middle strip 4200 mm 0.9 DL + 1.5 EQX
0.9 DL – 1.5 EQX
16. Width of Column strip 4200 mm 0.9 DL + 1.5 EQY
0.9 DL – 1.5 EQY
Zone III For all soil condition
Plan and 3D model of flat slab & grid slab (ETABS
SOFTWARE)
Loading to be considered for the analysis purpose
Sr. Loading Terrace Remaining
no. floor
1 Dead load 4.0 kN/m2 6.5 kN/M2 Flat slab
2
4.0 KN/m 4.0 KN/m2 Grid slab
2 Live load 1.5 kN/M2 4.0 kN/M2 Flat slab
1.5 kN/M2 4.0 kN/M2 Grid slab
3 Grid 4.0 kN/m2 @ parapet weight
10.0 kN/m2 @ regular floor weight
(for Flat slab & Grid slab)
No loading considered in internal beam for grid slab building
Plan of flat slab
Plan of grid slab
Method of analusis of building
Statis Analysis:-
Existing flat slab building is analyzed manually for static
load cases.since the given flat slab system satisfies all the
condition required by Direct Design Method(DDM),both the
ELEVATION OF FLAT SLAB methods of analysis are used viz. DDM, EFM ,and compared
factored moment for gravity load condition are given for
Load combination considered 600mm square column
1.5 DL + 1.5 LL
1.5 EQX + 1.5 DL
- 1.5 EQX + 1.5 DL
1.5 EQY + 1.5 DL
- 1.5 EQY + 1.5 DL
1.2 EQX + 1.2DL + 0.3 LL
- 1.2EQX +1.2 DL + 0.3 LL
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4. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
Details of Bending moment in slab panel specified design lateral force with partial load
factor 1.00 shall not exceed 0.004 times the
Sr. Design Negative Positive mome storey height. As per I.S. requirement it is
No Metho Moment Moment nt limited to 0.4% of the storey height. Drift control
d (KNm) (KNm) is necessary to limit damage to interior partition,
Exter elevator and stair enclosures, glass. & cladding
1 ior DDM 640 470 1110 systems
2 panel EFM 430 530 960 2. In this case storey height is 3600 mm. therefore
limited storey drift is calculated as
storey drift /3600 =0.004
Therefore, storey drift = 14.4 mm
Interi 3. In ETABS version 9.6.0 the ratio of (storey drift
3 or DDM 790 420 1210 / storey height ) is designated as storey drift this
4 panel EFM 930 350 1280 value should not exceed 0.004
4. After the dynamic analysis, combination which
has maximum drift is selected. It is (Dl + EQY)
Dynamic analysis since there is less stiffness for the building in Y-
1. Response spectrum method is used for analysis, direction, building deflect more in y- direction
Importance factor & response reduction factor 5. Storey drift of grid slab. Flat slab in Y-direction,
are considered as 1 & 5 respectively. By when placed in Zone III and in three soil
considering 12 modes mass participation of flat condition compared with graph.
slab building is achieved up to 96%(following Building type
table)
2. Therefore for all buildings 12 modes are Flat slab Grid slab
considered.
3. Ritz Vector analyses are used for analysis. Rigid ZONE III
diaphragm action is considered for analysis 1. Soil 1 (Rock or hard soil)
Center of mass & centre of rigidity coincides, due to 2. Soil 2 (medium soil)
regularity in the plan, mass and stiffness of the building. 3. Soil 3 (soft soil)
Centre of mass & centre of rigidity lies at (21m, 12.6m)
DRIFT -Y COMPARISEN ZONE III SOIL 1
Details of time period and mass participation for 16
flat slab 14
12
DRIFT (mm)
Mode Time % mass Cumulative
10
No, period participation Mass 8
participation 6
1 1.472185 76.6451 76.6451 4
2 1.318386 10.8657 87.5108 2
3 0.573172 2.3588 89.8696 0
1 2 3 4 5 6 7 8 9
4 0.55808 1.333 91.206
5 0.320090 1.1464 92.349 GRID SLAB 2.49 4.8 5.46 5.94 5.67 5.18 5.46 4.07 2.5
6 0.313189 0.87236 93.22136 FLAT SLAB 2.46 4.79 5.5 6.03 5.81 5.36 5.66 4.29 2.57
7 0.214571 0.73056 93.95192 DRIFT LIMIT 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4
8 0.2111013 0.6398 94.259172
9 0.149426 0.47539 95.06711 Graph 1
10 0.147395 0.35595 95.42306
11 0.087395 0.09812 95.52118
12 0.086613 0.0756 95.59678
Results:-
BUILDING DRIFT
1. Storey drift is defined as difference between
lateral displacement of one floor relative to the
other floor. As per IS. 1893-2002 CL.7.11.1; the
storey drift in any storey due to the minimum
278 | P a g e
5. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
DRIFT -Y COMPARISION ZONE III SOIL 2
SHEAR FORCE COMPARISION FOR FLAT
20 SLAB FOR ZONE III WITH THREE SOIL
CONDITION
DRIFT (MM)
15 900
10 800
700
5 600
SF (KN)
500
0 400
1 2 3 4 5 6 7 8 9
300
GRID SLAB 3.59 6.91 7.86 8.55 8.16 7.45 7.86 5.86 3.45 200
FLAT SLAB 3.53 6.89 7.91 8.67 8.35 7.71 8.13 6.16 3.7 100
DRIFT LIMIT 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4
0
1 2 3 4 5 6 7 8 9
Graph 2 ZONE III SOIL 1 7.0 28. 62 108 169 237 315 411 495
ZONE III SOIL 2 9.5 38. 84. 147 230 322 428 559 674
DRIFT - Y COMPARISION ZONE III SOIL 3
ZONE III SOIL 3 11. 47 104 181 282 396 526 687 827
20
DRIFT (MM)
Graph 4
15
10 SHEAR FORCE COMPARISION OF GRID
SLAB FOR ZONE III WITH THREE SOIL
5 CONDITIONS
0
1 2 3 4 5 6 7 8 9 800
GRID SLAB
700
5.38 10.3 11.7 12.8 12.2 11.1 11.7 8.79 5.18 600
SF (KN)
FLAT SLAB 5.29 10.3 11.8 13 12.5 11.5 12.2 9.24 5.55 500
400
DRIFT LIMIT 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4 14.4 300
200
Graph 3 100
0
Conclusion from graph (graph 1 to graph 3):- 1 2 3 4 5 6 7 8 9
1. All graphs clearly show that grid slab has less drift
compared to flat slab. Drift or relative displacement ZONE III SOIL 1 6.1 24. 54. 94. 148 207 275 359 437
of a storey is the ratio of base shear experienced by ZONE III SOIL 2 8.3 33. 73. 129 201 282 374 488 586
that storey to total stiffness of column at that storey is
same for all three type of slab. Maximum drift ZONE III SOIL 3 10. 41. 90. 158 247 346 459 600 719
indicate maximum base shear.
Graph 5
2. Drifts of flat slab and grid slab are approximately
Conclusion from graph (graph 4 & 5):-
equal up to storey 4.
1. Flat slab experience maximum shear force, where as
3. Comparing strata condition, building on soft soil (soil
grid slab experiences less shear force. Shear force
3) deflect more than other to soil condition.
experienced by flat slab is 14 % higher than that of
4. All slab deflect within the limit when strata of type
the grid slab for all combination of zone and soil
one i.e. rock, or hard soil.
conditions.
5. Storey four and storey seven experience maximum
2. There is definite correlation between increase in
drift but not exceeding the drift limit. This shows that
shear force and storey drift with change in soil
column stiffness requirement of storey four and seven
conditions for particular type of slab e.g. flat slab
is greater than that or remaining storey.
building in medium soil condition (soil 2)
SHEAR FORCE:-
experiences 36% more drift and 36% more shear
Shear force experienced by each storey of flat slab and grid
force than building located on hard strata, where flat
slab is compared based on different soil condition. Existing
slab building on soft soil condition both of them are
building is located in zone III.
67% more. Similarly in case of grid slab also.
279 | P a g e
6. Sandesh D. Bothara, Dr.Valsson Varghese / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 4, July-August 2012, pp.275-280
DESIGN MOMENT:-
Comparison of maximum moment obtained manually and by software for flat slab
Sr. Design Negative Positive Moment Software
No Method Moment Moment (KNm) (KNm)
(KNm) (KNm)
1 Exterior DDM 640 470 1110 1085
2 panel EFM 430 530 960
3 Interior DDM 790 420 1210 1132
4 panel EFM 930 350 1280
Comparison of maximum moment obtained manually and by software for grid slab
Manually Software
Maximum moment 1813 1956
(KNm)
CONCLUSION:-
1. Existing flat slab building performs well in zone III and
with all soil conditions. 4.. Ductile Detailing of Reinforced Concrete Structures to
4
2. For improving drift conditions of flat slab in higher Seismic Forces IS 13920:1993
seismic zones lateral load resisting system should be
coupled with slab column frame, and or stiffness of 5. Durrani A. J.; Mau S. T., AbouHashish A. A., and Yi
column should be increased. Li, “Earthquake Response of Flat-Slab Buildings,”
3. Since soil condition drastically affects the behavior of Journal of Structural Engineering, Vol. 120, No. 3,
building during earthquake, careful investigation of March, 1994.
strata before selecting type of construction must be
done. 6. M.Anitha, B.Q.Rahman, JJ.Vijay, “Analysis and
4. The negative moment’s section shall be designed to Design of Flat Slabs Using Various Codes”
resist the larger of the two interior negative design International Institute of Information Technology,
moments for the span framing into common supports. Hyderabad (Deemed University) April 2007.
5. Drops are important criteria in increasing the shear
strength of the slab.
6. Negative moment is highly concentrated within the 7. M. H. Haraj, K. A. Soudki, and T. Kuds,
critical perimeter of the column, positive moment is “Strengthening of Interior Slab-Column Connections
much more uniform with maximum at column Using a Combination of FRP Sheets and Steel Bolts.”
centerline. Journal of Composites for Construction, Vol. 10, No.5,
October 1, 2006.
REFERENCES:-
1. B. A. Izzuddin, X. Y. Tao; and A. Y. Elghazouli, 8. M. Altug Erberik and Amr S. Elnashai “Loss
“Realistic Modeling of Composite and Reinforced Estimation Analysis of Flat-Slab Structures.” Natural
Concrete Floor Slabs under Extreme Loading.” I: Hazards Review, Vol. 7, No. 1, February 1, 2006
Analytical Method Journal of Structural Engineering,
Vol. 130, No. 12, December 1, 2004.
2. Criteria for Earthquake Resistant Design of Structures 9. Indian standard “Plain & Reinforced Concrete Code of
Part 1 General Provisions and Buildings (Fifth Practice” Fourth Revision IS: 456:2000..
Revision) IS 1893(part 1):2002.
3. Dr. Ram Chandra, Virendra Gahlot, “Elements of Limit 7. Softwares:- ETABS 9.60
State Design of Concrete Structures” Scientific
Publishers (India), 2004.
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